200 



E. Jorgensen. 



Dhtrihution: Balearic Isles. The main species known from 

 the coast of the isle of Skye. 



B. aurita (Lyngb.) Bréb. 



Cf. above p. 99. 



Probably derived from the plankton. 



Frequent: Stamsund +, Svolvær + c, Stene r -|-. 



Dixtrihiiiion: CL above p. 99. 



B, rhoiubiis (Ehrb.) W. S.m. 

 W. Sm. Brit. Diat. II, ]i. 4!t, pi. 45, f. 320. Denticella r. Ehrb. 



yar. trigona Cl. Van Heurck Synops, pl. 09, f. 2. 



Very rare: Svolvær r. 



Distriliidion: Coasts of the North Sea and Western Europe. 

 Finmark (Cleve). 



B. turgida (Ehrb.) \V. Sm. 



W. Sm. Brit. Diat. II, p. .50, pi. t)2, f. 38. Vax HEaRCic Synops, pl. 104, figs. 1, 2. 



Cerofnulun t. Ehrb. 



Very rare: Svolvær r r. 



Distribution: Coasts of the North Sea and Western Europe. 



B. Smithii (Ralfs) V. H. 



Van Heueck Synops, p. 207, pi. 105, tigs. 1—2. A. Schmidt Atlas pi. Ill), 



figs. 5 — 6. Ceratmlus S. Ealfs in Pritch. p. 847. 



Very rare: Moskenstrømmen rr, Svolvær i-. 

 Didribution: Coa.sts of the North Sea and Western Europe. 

 Spitsbergen? ( Cleve i. 



B. antfdiluyiana (Ehrb.) V. H. 



Van Heurck Synops, pl. 109, tigs. 4—5. Amphifetras a. Ehrb., Mikrogeol. 



pi. 21, f. 25 a— c. 



Rather frequent: Moskenstrømmen -f > Stamsund r, Raftsund r, 

 Gaukværø r, Stene r. 



Didrihution : Common spedes, cosmopolitan; very rare, how- 

 ever, iu arctic reyions: Spitsbei'ijen (rr, Cleve). 



B. lata ((iREv ). 

 Triceralium 1. (Irev. Trans. Micr. So(^ 1865, p. 103, \Å. 9, f. 20. A. Schmidt 

 Atlas, pl. 77, figs. 38—39. ÅmphUetrais 1. De Toni Syll. vol. II, sect. 3, p. 901. 



Very rare: Raftsund r. \'cry similar to the figures referred 

 to in S.ciimitit's Atlas. Side of the tctra.y-onc 07 |).. Marginal 

 pearls 5 on 10 |)-; tlie I'ows of sti-iæ in tiio corners somewhat 

 radiating, 10 on 10 [>.. 



Distiibntion : Tropical species, according to De Toni (1. c.) 

 only known from Singapore and North Celebes. 



n. far us IKURB.) V. H. 



Van Hel'rck Synops, pi. 107, figs. 1—4. Trurrtitiniii facus Khrb. A. Schmidt 



Atlas, ]il. 82, f. 2. 



Very rare: Rartsuiid. rr. Side of the triangle 92 |).; 2 ai'eoles 

 on 10 1».. 



JJititriljution : Rathci' common sjjccios, cosmopolitan on tropical 

 and temperate coasts. Spitsbergen i('li;ve, ,,doubtful as an arctic 

 species"). 



B. arctica (Brightw.). 



Triceratium a. Brightw. Micr. Journ. 1853, p. 250, pi. 4. t'. 11. A. Schmidt 



Atlas pi. 79, figs. 12—13. 



Very rare: Stene r. 



forma balæna (Ehrb.). 

 Zygoceros b. Ehrb. Mikrogeol. pi. .35 A, XXIII, C. 17. Bitlduljihia h. Brightw. 

 Micr. .Journ. VII (1859), p. 181, ])1. 9, f. 15. Van Heurck Synops.pl. 112, f. 1. 



Very rare: Stene r. 



Distribution: Arctic regions. Vancouver; Cape of Good Hope 

 (De Toni Syll. p. 921). 



B. formosa (Brightw.). 



TriceratiHiii f. Brightw. Grun. in Cleve et Grun. Arkt. Diat. pp. 111 — 112. 



A. Schmidt Atlas, jil. 79 f. 2. 



Very nearly related to the preceding species, from wliich it 

 differs chiefly in having the centre of the valve irregularly punctate, 

 not areolate, with scattered puncta smaller than the neighbouring 

 areoles. 



Very rare: Raftsund r. 



fonna balæna. 



An-swering to the forma baiwna of the preceding species. 

 Very rare: Raftsund r. 



B. alteriians (Bail.) V. H. 



Van Heurck Synops, p. 208, pl. 113, figs. 4—7. Triceratium a. Bail. Micr. 



Obs. p. 40, figs. 55— 5tx 



Very rare: Stamsund r r. 



Distribution: Western Europe. West Indies. 



B. punctata (Brightw.) V. H. 

 Van Heurciv Synops, pl. 109, f. 10 (forma 3-tjomi). Triceratium p. Brightw. 

 Micr. .Journ. 1856, p. 275, pl. 17, f. 18, non Biihhdphia punctata Grev. 1864. 



Very rare: Gaukværø, rr. Irregularly punctate with puncta 

 very different in size, shape and distance from each other, on an 

 average 5 on 10 [a. Side of the triangle 10 \i. 



Distribution: Tropical coasts of America, Africa and Asia. 

 The nearly related B. sculpta (Shade.) \'. H., wiiich by De Toni 

 1. c. p. 9-4-4 is Considered to belong to the same species, occurs in 

 Western Eui'ope, the Skagerack, and the Mediterranean. 



B. nohilis (Wurx.). 



Triceratium n. Witt. Diat. Siniliirsk 18S5, p. :!4. pi. 10, f. 3: pi. 11, figs. 4. 7. 



A. Schmidt Atlas pi. 150, f. 25. Xon Biddulphia nabilis Brun 1889. 



A specimen very similar to the figure referred to in Schmidt's 

 Atlas (from Archangel) was found: Gaukværø r r; Stene r r. 

 Large puncta, irregular in size and shape, intermingled with minute 

 ones. Near the margin, larger areoles. in tlie centre, a con- 

 spicuous inward pointing spine is found. Side of the triangle 5(i ;'. 



A nearly related species is Triceratium Hvibcrgii Qinvfi., V. 11. 

 Synops, pl. 112, figs. 9 — 11 (from Mors). 



Distribution : Only known fossil from Simbirsk. Perhaps also 

 fossil in my samples (as is probably also the case with some of the 

 other species). 



